A grouping of coral islands is known as an atoll. Atolls can be a collection of small islands or one continuous island. They form from the remnants of undersea volcanoes.Know More
A group of coral islands, or an atoll, form as underwater volcanoes grow and get closer to the surface, effectively raising the sea floor. Once within reach of sunlight in sufficient amounts, corals and other marine life take hold. As volcanoes erode due to wave action and wind, the hard corals remain. Because of this, most atolls are ring-shaped. Islands form over time as corals die and their hard exteriors break down into the sand. Coral islands have distinguishing characteristics, such as high elevations, reef-front terraces and mostly submerged reefs.
The ring shape of the atoll is not always at a consistent height, as different areas of the volcano erode at different times. In such cases, a collection of coral islands is formed. Additionally, if a large section of the volcano falls away, crescent-shaped atolls begin to develop. Because of the way they are formed, atolls partially or completely enclose a central lagoon. These lagoons are oases for marine life, as they are sheltered from the harsh conditions of the open ocean.Learn more about Australia
The islands that make up the West Indies are as follows: Cuba, Jamaica, Hispaniola (Haiti and the Dominican Republic),and Puerto Rico, known collectively as the Greater Antilles; and the Virgin Islands, Anguilla, Saint Kitts and Nevis, Antigua and Barbuda, Montserrat, Guadeloupe, Dominica, Martinique, Saint Lucia, Saint Vincent and the Grenadines, Barbados, and Grenada, the Lesser Antilles. These are the two main geographical regions that make up the West Indies.Full Answer >
The Australian continent contains only one country, called Australia. The country is over 7.6 square kilometers in size, making it the sixth largest country in the world.Full Answer >
Australia has not adopted an official national animal, but has designated the red kangaroo and the emu as Australia's "native animals." These two species appear on its shield, the Commonwealth Coat of Arms.Full Answer >
The capital of Australia is Canberra, while the largest city is Sydney. Canberra is located in southeastern Australia and includes an area of about 300 square miles. Canberra had a population exceeding 380,000 people, as of 2013. Sydney is located on the southeastern coast and including around 4,800 square miles.Full Answer >